IIAE CONFERENCE SYSTEM, The 1st IEEE/IIAE International Conference on Intelligent Systems and Image Processing 2013 (ICISIP2013)

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Development of LED Road Traffic Signal Considering Washout Phenomenon
Kazutaka Hongo, Kentarou Hayashi, Yoshinori Akinaga, Masahiro Kourogi, Makoto Miyauchi, Seiichi Serikawa

Last modified: 2013-10-01


Blue LED is recently mass-produced; road traffic signal head using LED system began to be used. The LED signal head has advantages such as energy saving and long life. However, the newly proposed instrument LED signal head is difficult to reduce problems such as washout phenomenon. In this paper, we have proposed reduction of washout phenomenon of LED signal head by using the LED element 192 and low-reflection black plate on a blank area between the elements. In the measurement of light intensity distribution and luminance uniformity, it was confirmed that the LED type signal head we proposed satisfy the conditions described in the traffic signal lighting specification by the National Police Agency. The visibility of signal head are improved ,as apparent from the result of phantom ratio.


Road traffic signal head, washout phenomenon., Phantom ratio


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